Acrylonitrile copolymers



' Patented Aug. 25, 1953 4 UNITED. v STATES PATENT OFFICE A a 1 I12,650,151

ACRYLONITRILE COPOLYMERS George E. Ham, Dayton, Ohio, assignor, by mesneassignments, to The Chemstrand Corporation, l p a corporation ofDelaware No Drawing. Application April 22, 1950, Serial N0. 157,637

18 Claims. 1

spinning operations.

'It is known that copolymers ofin excess of 85 per cent acrylonitrileand up to 15 per cent of other monomers have excellent fiber-formingproperties. It is further known that by the proper selection of thecomonomer, the copolymers and fibers prepared therefrom are made capableof More reacting with acid dyestuffs, whereby useful colored productsare obtainable. Most of the dye- .able acrylonitrile polymers known tothe published literature involve the use of comonoineric substances,which are costly and available only in limited quantities. Accordingly,dyeable fibers are prohibitively expensive and non-competitive.

The primary purpose of this invention is to provide a method ofpreparing fibers of improved dye receptivity. A further purpose is toprovide methods of converting acrylonitrile copolymers" intodye-receptive'polymers by an efliclent and economical procedure. A stillfurther purpose is to provide new copolymers of acrylonitrile havingunusual properties as are hereinafter described. It has been found thatnew and useful copolymers can be obtained by copolymerization ofacrylonitrile with allyl glycidyl ether, methallyl glycidyl ether orp-chloroallyl 'glycidyl ether. The useful polymers are those of 80 to 98per cent of acrylonitrile and from two to per cent of the unsaturatedglycidyl ether. Since the glycidyl ethers may hydrolyze when present inlarger proportions in the polymerization reaction vessel, the copolymersof from two to ten per cent have been found to be more useful.-

The acrylonitrile-unsaturated glycidyl ether polymers may include smallproportions of other monomers interpolymerized therewith, for examplevinyl acetate, vinyl chloride, styrene, methacrylonitrile, vinylpyridine, methyl methacrylate, and diethylmaleate. The quantity of thecomonomer present in polymerized form in the acrylonitrile polymer mustnecessarily be small, since at least 80 percent of acrylonitrile is rei2 a quired to produce fibers with desirable tensile properties, andsince at least two percent of the glycidyl ether is required.Accordingly, copolymers of up to 18 per cent of the comonomer, ormixtures of comonomers, are useful.

The' new copolymers of acrylonitrile and the glycidyl ethers may beprepared by any polymerization procedure, but the preferred practiceutilizes a modified aqueous emulsion polymerization whereby finelydivided solid polymers capable of use directly in fiber operations, areobtained. The emulsion polymerization procedure may utilize batchprocedures wherein the monomers are charged with an aqueous mediumcontaining the necessary catalyst and dispersion agents. How ever, thepreferred procedure involves a semi-continuous procedure, in which amixture of monomer is charged to an aqueous medium maintained underconditions necessary to effect polymerizatio'n. Obviously, entirelycontinuous procedures may also be used in which the monomers aregradually introduced to the reactor and the cothroughout the reactionfor the purpose of maintaming a moreuniform concentration of catalyst inthe reaction mass. The latter method is preferred because it tends tomake the resultant polymer more uniform in its chemical and physicalproperties. Although the uniform distribution of the reactantsthroughout the reaction mass can be achieved by vigorous agitation. itis generally desirable to promote the uniform distribution of reagentsbyusing wetting agents, or emulsion stabilizers. Suitable reagents forthis purpose are the water soluble salts of fatty acids, such as A widevariation in the quantity dium oleate and potassium stearate, mixturesoi." water soluble fatty acid salts, such as common soaps prepared-bythe saponificationof animal an vegetable oils, the amine soaps, such ass of triethanolamine and dodecylmethylamine, salts of rosin acids andmixtures thereof, the water soluble salts of half esters of sulfuricacid and long chain aliphatic alcohols, sulfonated hydrocarbons, such asalkyl aryl sulfonates, and

a other of the wide variety of wetting agents,

h are in general organic compounds containing both hydrophobic andhydrophilic radicals. The quantity of emulsifying agent will dea of thedispersion which is primarily concerned with the ease of filtration, thewater to monomer ratio which must necessarily be low for the mosteconomical production, and the yield and conversion of the monomers tocopolymer.

The emulsion polymerizations are preferably conducted in glass orglass-lined vessels which are provided with a means for agitating thecontents. Generally rotary stirring devices are the most efiective meansof insuring the intimate contact of the reagents, but other means may besuccessfully employed, for example by rocking or tumbling the reactors.The polymerization equipment generally used is conventional inthe art,and the adaptation of a particular type of apparatus to the reactioncontemplated is within the province of one skilled in the art.

The optimum polymerizations for fiber formation involve the use ofpolymerization regulators to prevent the formation of polymer units ofexcessive molecular weight. Suitable regulators are the alkyl and arylmercaptans, carbon tetrachloride. chloroform, dithioglycidol andalcohols. The regulators may be used in amounts varying from .001 to twopercent on the weight of the monomer to be polymerized.

When the polymerization is complete the po1ymer is separated from theaqueous medium by any of the conventionally used methods. When theoptimum procedures above described are used the polymer may be separatedfrom the aqueous phase by filtration. The resulting polymer in eithercase may require washing operations to fonate, dlmethylsulfate, n-butylbromide, may be remove traces of soluble catalyst or dispersing agent.

The solid granular copolymers of acrylonitrile and the glycidyl ethersare useful in the reparation of fibers by conventional methods. Thepreferred practice involves the preparation of spinning solutions bydispersing the polymer in suitable solvents, for exampleN,N-dimethylacetamide, N,N-dimethylformamide, gamma-butyrolactone andethylene carbonate. The polymer solutions are fabricated into fibers byextrusion through a suitable die or a spinneret containing a pluralityof minute apertures into a medium which removes the solvent and'causesthe polymer to precipitate into a continuous linear form. The saidmedium may be liquid, for example water, or aqueous solutions of acids,gases or salts, or it may be a gaseous medium, for example air or anygas which is inert with respect to the polymer.

In order to convert the fibers into a dye receping the primaryconversion are amines which' containat least one active hydrogen. Thus,primary amines, such as methylamine, n-butylamine, aniline orcyclohexylamine, or secondary amines, such as dimethylamine,diethylamine, dibutylamine, N-methylaniline and N-methylcyclohexylamineare suitable. The amine or ammonia derivatives are thereafter reactedwith agents suitable for converting the nitrogen into a quaternaryammonium salt form, the quantity required depending upon the number ofreplaceable hydrogens contained in the basic copolymer. For thisreaction reagents, such as chloroacetic acid, methyl chloroacetate,methyl toluenesulused. In general the quaternizing agents may bealiphatic compounds containing halogen substituents or they may beesters of oxygen containing sulfur acids, which acids have ionizationconstants in excess of 10-. Similarly, other agents for convertingaliphatic nitrogen atoms into quaternary salts may be used.

The above after-treatment for the purpose of converting the copolymerinto dyeable form has been set forth with respect to the treatment ofthe previously prepared fibers. If desired the polymers may be convertedinto dyeable form prior to the preparation of the fibers. Thus. thecopolymers of acrylonitrile and the various unsaturated glycidyl ethersmay be reacted with amines and quaternized in the solid state asobtained from the polymerization reaction. In such cases, however, thereaction preferably involves the use of secondary amines, such asdimethylamine and diethylamine, because the presence of ammonia orprimary amines in the spinning solution often results in gelationwhereby unspinnable solutions result.

A preferred fiber preparation method involves the dispersion of theuntreated copolymer in a suitable solvent, for example N,N-dimethylacetamide, and thereafter treating the spinning solution withsecondary amines and quaternizing agents. Here again the use ofsecondary amines, such as dimethylamine and dibutylamine is required,because the presence of ammonia and primary amines often induces thegelation of the spinning solution.

A further procedure for fiber preparation involves the preliminarypreparation of aminetreated fibers and dyeing them in conventional dyebaths to which the quaternizing agents have been added. By thisprocedure the amine treatment may be executed on the solid polymer, inthe spinning solution, or on the spun fibers.

An alternative procedure for preparing dyeable,

copolymers of acrylonitrile and 'glycidyl ether, involves thepreliminary treatment with amines either before or after fiberpreparation, and

thereafter dyeing them in a dye bath containing To develop optimumdyeability the The reaction by which the allyl glycidyl ether copolymeris converted to a dyeable composition by treatment first. with asecondary amine and thenwith an alkyl' halide, is believed to be as;

The reaction whereby the allyl glycidyl ether copolymer is converted toa dyeable composition by thiourea treatment is believed to be as fol:

The reaction of the allyl glycidyl ether copolymer with2-mercaptobenzothiazole followed-by reaction with an alkyl halide isbelieved to be,

as follows:

The modified compositions shown above possess the common features ofbeing capable of undergoing anionic exchange with acid dyes.

Further details or the invention are set forth 1 with respect to thefollowing specific examples.

Example '1 A mixture of 92 parts of acrylonitrile and eight through awater bath and'stretched in a steam the resulting copolymer slurry wassteam-distilled to remove unreacted monomer, filtered,

washed withv water and dried. Ayield of 84.2

parts of copolymer ofapproximately 94 percent acrylonitrile-six percentallyl glycidyl ether wasv obtained.-

A 16 per cent solution of this copolymer in dimethylacet'amide wasprepared and spun through a -hole spinneret (0.005" holes) into amixture of 60 per cent dimethylaoeta'mide- 40 per cent water. The fiberwas then passed tube 330 per cent. The fiber possessed a tenacity of 3.3grams per denier, elongation'of 7-8 per cent, and boil shrinkage of 6.7per cent.

\ Example'2 One hundred parts of a 16- percent solution of the copolymerof Example 1 was treated with eight parts of a 12-per centdimethylamine' solution in dimethylacetamide and heated for six hours at68 C. To this solution was added 1.08'

parts of chloro'acet ic acid dissolved in two parts ofdimethylacetamideand thesolution was heated at 68? C. for five hours. Fibers spun fromthis solution were stretched 4.17 times and possessed a tenacity of 3.2grams per denier, elongation of seven per cent and a boil shrinkage of8.6 per cent. e

Agram sample of fiber skein' was dycdwith a solution obtained by mixingone ml. of two per cent .Wool Fast Scarlet solution, "'5 mls. of

' denier and an elongation of eight percent. This three percent sulfuricacid,'and 40 mls. of water.

After the skein was dyed for four hours at 100 CL'a deep scarlet colorwas produced. The skein had adsorbed 8 mgs..of Wool Fast Scarlet.

Example 3 A16 percent solution (100 parts) of the copolymer of Example 1was treated'with eight parts of 12 per cent dimethylamine-= dissolved indim'ethylacetamide and heated for five hours at 68 C. Chloroacetic'acidwas added as in Example 2, and the solution was immediately spun. Afterthe ',fiber, was stretched 3.3 times it was found to possess 'a tenacityof 2.4 grams per sample was rendered readily dyeable by the addition ofan equal weight of chloroacetic acid to the dyebath.

Example-4 'Copolymerization of a mixture of 88 parts of acrylonitrileand twelve parts of allyl glycidyl ether as in Example 1', 8' produced acopolymer of approximately 92 per cent acrylonitrile and elght ,percent"'allyl glycidyl ether in a yield of 80.4 per cent. On spinning a 17per cent soluparts of allyl glycidy'l etherwas added'continu- 5 ously toa stirred reaction flask equippedwith a reflux condenser, containing 370parts of distilled water and 0.1 part of a sodium salt or a sulfonatedmahogany soap, at'75-"0. over a period of 1.5 hours. During the monomeraddition a solution of 0.5 partof potassium per'suli'ate in- 30 parts ofwater was added as six increments at equal time intervals. After 0.5hour reflux possessed a tenacity of 3.1 grams per denier, elongation of9-10 per cent, and boil shrinkage "per cent was obtained.

' 'tion' of this resin in dimethylacetamide solution as in Examplel, andstretching 3.16 times, a fiber of a tenacity of 2.2 grams per denier,elongation of 8-9 per cent,and boil shrinkage of 9.2

could not be dyed with Wool Fast "Scarlet.

Example 5 The unmodified fiber.

.of 10.7 per cent. Though the fiber was not Example 6 A one gram skeinof the copolymer of 92 per cent acrylonitrile-eight. per cent allylglycidyl ether produced as in Example 4, were dyed with a mixture of 1m1. of two percent Wool Fast Scarlet, 5 mls. of three per' cent sulfuricacid. one gram of thiourea, and 40 mls. of water. A deep scarlet colorwas produced on the fiber and dyebath exhaustion was obtained within 40minutes, at 100 C. When thiourea was omitted from the dyebath virtuallyno dye was absorbed by the fiber. Good dyeing with Acid Green CC ExtraConc. was also obtained when thiourea equal to the fiber weight wasadded to the dyebath.

Example 7 To 100 parts of a 17 percent solution of the copolymer of 92per cent acrylonitrile and eight per cent allyl glycidyl ether was addeda solution of 2.08 parts of mercaptobenzothiazole in four parts ofdimethylacetamide with stirring. The solution was heated for five hoursat 70 C. and spun as in Example 1. The fiber after stretching 4.55 timeswas found to possess a tenacity of 2.5 grams per denier, elongation offive per cent, and boil shrinkage of 12 per cent. On dyeing for fourhours with Wool Fast Scarlet in the presence of an equal weight ofchloroacetic acid, good color development on the fiber was obtained.When the chloroacetic acid was omitted from the dyebath, little dye wasadsorbed by the fiber.

Example 8 A skein of the copolymer of 92 percent acrylonitrile-eight percent allyl glycidyl ether was immersed in cyclohexylamine for threeminutes at 110 C. The skein was washed with acetone and water and dried.Fairly good dyeing with Wool Fast Scarlet was obtained.

The invention is defined by the following claims.

I claim:

1. A copolymer of at least 80 per cent by weight of acrylonitrile andfrom two to 20 per cent of a compound of the group consisting of allylglycidyl ether, methallyl glycidyl ether and p-chloroallyl glycidylether. j

2. A fiber of a copolymer of 90 to 98 per cent by weight ofacrylonitrile and from two to ten per cent of a compound of the groupconsisting of allyl glycidyl ether, methallyl glycidyl ether andfi-chloroallyl glycidyl ether.

3. A copolymer of 80 to 98 per cent by weight of acrylonitrile and fromtwo to 20 per cent of allyl glycidyl ether.

4. A copolymer of 80 to 98 per 'centby weight of acrylonitrile and fromtwo to 20 per cent of methallyl glycidyl ether.

5. A copolymer of 80 to 98 per cent by weight of,-acrylonitrile and fromtwo to 20 per cent of p-chloroallyl glycidyl ether.

- 6. A fiber of a copolymer of 90 to 98 per cent by "9. A dyeablecopolymer 01-80 to 98 per cent by weight of acrylonitrile and from twoto 20 per cent of-a compound of the group consisting of allyl glycidylether,.methallyl glycidyl ether and p-chloroallyl glycidyl ether, saidcopolymer having been contacted first with a. compound of the groupconsisting of ammonia, primary amines and secondary amines to form aminogroups, and thereafter by an agent capable of converting the aminogroups into quaternary ammonium salt groups. a

10. A dyeable copolymer of 80 to 98 per cent by weight of acrylonitrileand from two to 20 per cent of a compound of the group consisting ofallyl glycidyl ether, methallyl glycidyl ether and p-chloroallylglycidyl ether, said copolymer having been contacted with a secondaryamine and thereafter with a compound of the group consisting ofaliphatic halogen containing compounds and esters of theoxygen-containing sulfur acids,

which acids have ionization constants in excess 11. A dyeable fiber of acopolymer of 80 to 98 per cent by weight of acrylonitrile and from twoto 20 per cent of a compound of the group consisting of allyl glycidylether, methallyl glycidyl ether and p-chloroallyl glycidyl ether, saidfiber having been contacted with a compound of the group consisting ofammonia, primary amines and secondary amines to form amino groups, andthereafter contacting the fiber with an agent capable of converting theamino groups into quaternary ammonium salt groups.

12. A dyeable fiber of a copolymer of 80 to 98 per cent by weight ofacrylonitrile and from two to 20 per cent of a compound of the groupconsisting of allyl glycidyl ether, methallyl glycidyl ether andfi-chloroallyl glycidyl ether,said fiber 'having been contacted with-acompound of the group consisting of thiourea and alkyl substitutedthioureas.

' 13. A colored fiber of a copolymer of 80 to 98 per cent by weight ofacrylonitril and from two to 20 per cent of a compound of the groupconsisting of allyl glycidyl ether, methallyl glycidyl ether andfl-chlorallyl glycidyl ether, said fiber having been dyed with an aciddyestufi' in the presence of a compound of the group consisting ofthiourea and alkyl substituted thioureas.

14. A method of preparing a dyed fiber, which comprises contacting afiber of a copolymer of 80 to-98 per cent by weight of acrylonitrile andfrom two to 20 per cent of acompound of the group consisting of allylglycidyl ether, methallyl glycidyl ether and ,S-chloroallyl glycidylether, with a compound of the group consisting of primary amines,secondary amines and ammonia, to convert the epoxy group into an aminoradical. thereafter contacting the fiber with an agent capable ofconverting the amino group into a 15. A method of preparing a dyedfiber, which comprises contacting a fiber of a copolymer of 90 to 98 percent by weight of acrylonitrile and from two to ten per cent of acompound of the v group consisting of allyl glycidyl ether, methallylglycidyl ether and -B-chloroa1lyl glycidyl ether,

with a compound of the group consisting of pri-' capable of convertingthe amino group into a compound of the group consisting of primary,

amines, secondary amin s and ammonia, to convert the epoxy group into anamino radical,

I thereafter contacting the fiber with an agent capable of convertingthe amino group into a quaternary ammonium salt group, and contactingthe fiber with an acid dyestufi.

1'7. A method of preparing a dyed fiber, which comprises contacting afiber of a copolymer of 90 to 98 per cent by weight of acrylonitrile andfrom two to ten per cent of methallyl glycidyl ether, with a compound ofthe group consisting of primary amines, secondary amines and ammonia,to. convert the epoxy group into an amino radical,

10 thereafter contacting the fiber with an agent capable of convertingthe amino group into a quaternary ammonium salt group, and contactingthe fiber with an acid dyestufi.

18. A dyeable fiber of a copolymer of 80 to 98 per cent by weight ofacrylonitrile and from 2 to 20 per cent of a compound of the groupconsisting of allyl glycidyl ether, methallyl glycidyl ether andbeta-chloroallyl glycidyl ether, said fiber having been contacted firstwith mercaptobenzothiazole, and thereafter with an agent capable ofconverting the heteronitrogen atom of the mercaptobenzothiazole into aquaternary ammonium salt group.

GEORGE E. HAM.

References Cited in the file .of this patent UNITED STATES PATENTSNumber

1. A COPOLYMER OF AT LEAST 80 PER CENT BY WEIGHT OF ACRYLONITRILE ANDFROM TWO TO 20 PER CENT OF A COMPOUND OF THE GROUP CONSISTING OF ALLYLGLYCIDYL ETHER, METHALLYL GLYCIDYL ETHER AND B-CHLOROALLYL GLYCIDYLETHER.